1. Field of the Invention
The present invention relates to a plate tube type heat exchanger using porous fins manufactured by a foam metal.
2. Description of the Background Art
A heat exchanger is a device performing a heat exchanging between two fluids, for example, a gas and a liquid, or a gas and another gas. The heat exchanger utilizes heat transmission to convert a low temperature fluid into a high temperature fluid and its industrial significance is on the increase in the related industries.
In particular, when heat exchanging is required between a gas and liquid, a heat exchanger using fins at its gas side may be employed so as to decrease a thermal resistance and increase the area exposed to the gas.
Conventional heat exchangers employs a variety of fin configurations including offset fins, wave fins and louvered fins.
An offset fin is formed by staggering adjacent aluminum plates or copper plates to obtain slits therebetween. A wave fin is formed with an undulating wave shape. A louvered fin is formed with angled louvers on a plate and it improves a mixing effect of air passing therethrough and eliminates multistage thermal boundary layers to thereby enhance heat transfer.
Among such fin configurations, the louvered fin is known as providing the best performance. For this reason, the louvered plate type heat exchanger is generally applied to an evaporator, a condenser and a heater core for air conditioning in an automobile requiring a compact type heat exchanger and for releasing heat of engine cooling water.
FIG. 1 illustrates an example of a plate tube type heat exchanger using louvered fins according to the conventional art. As shown therein, the heat exchanger using louvered fins includes a fluid path inlet 1, an inlet tank 2, plate tubes 3, fins 4, a tank 5, an outlet tank 6, and a fluid path outlet 7.
Here, the thermal resistance of the fins 4 through which air passes is the most influential component which decreases the efficiency of heat transmission, and accordingly there have been continuous improvements sought with regard thereto.
However, the conventional plate tube type heat exchanger using louvered fins is manufactured such that a thin aluminum plate of around 0.1 mm in thickness is louvered in multiple stages and continually folded accordingly, thereby complicating its manufacture.
Further, due to its structural weakness, the conventional heat exchanger may be bent when exposed to an impact, and thus there is a demand for a new type heat exchanger having attributes such as a better heat transmission, a structural ruggedness and a simplified manufacturing process.